Osteoarthritis (OA) is the most prevalent chronic joint condition. The knee is the second most commonly affected joint by OA (after the hand) and has prevalence in older people. Numerous studies also show that obesity is a strong risk factor for the development of knee OA. When symptoms are present, knee OA can be a major cause of physical disability. This study will test the relative effica-cies of exercise, wieght loss and a combined intervention in the management of osteoarthritis of the knee in older obese subjects.